The use of electronics devices and mobile electronics devices continue to proliferate. Many different types of electronics devices are currently available. A laptop computer, also known as a notebook computer, is a personal computer designed for mobile use. A laptop includes most of the typical components of a desktop computer, including a display, a keyboard, a cursor control device such as a touchpad, speakers, and a battery. The laptop is configured as two panels that fold open and closed by a hinge. This is often referred to as a clamshell form factor. The first panel includes the display, and the second panel includes the remaining components including the keyboard, touchpad, and device electronics. The outer portions of each panel form a protective cover for the laptop when closed.
A tablet laptop computer is a variation of the laptop computer, having a complex joint between the two panels that enables the display panel to twist and then lay flat on the keyboard panel such that the display is facing outward although the two panels are folded together. The display panel in the tablet laptop has a touchscreen display.
A touchscreen is a display that detects the presence, location, and pressure of a touch within the display area, generally by a finger, hand, stylus, or other pointing device. The touchscreen enables a user to interact with the display panel directly without requiring any intermediate device, rather than indirectly with a keyboard, a mouse, or a touchpad. Touchscreens can be implemented in computers or as terminals to access networks. Touchscreens are commonly found in point-of-sale systems, automated teller machines (ATMs), mobile phones, personal digital assistants (PDAs), portable game consoles, satellite navigation devices, and information appliances.
There are a number of types of touchscreen technologies. A resistive touchscreen panel is composed of several layers including two thin metallic electrically conductive and resistive layers separated by thin space. When some object touches the touchscreen panel, the layers are connected at a certain point. In response to the object contact, the panel electrically acts similar to two voltage dividers with connected outputs. This causes a change in the electrical current that is registered as a touch event and sent to the controller for processing.
A capacitive touchscreen panel is coated, partially coated, or patterned with a material that conducts a continuous electrical current across a sensor. The sensor exhibits a precisely controlled field of stored electrons in both the horizontal and vertical axes to achieve capacitance. The human body is also an electrical device that has stored electrons and therefore also exhibits capacitance. When a reference capacitance of the sensor is altered by another capacitance field, such as a finger, electronic circuits located at each corner of the panel measure the resultant distortion in the reference capacitance. The measured information related to the touch event is sent to the controller for mathematical processing. Capacitive sensors can either be touched with a bare finger or with a conductive device being held by a bare hand. Capacitive sensors also work based on proximity, and do not have to be directly touched to be triggered. In most cases, direct contact to a conductive metal surface does not occur and the conductive sensor is separated from the user's body by an insulating glass or plastic layer. Devices with capacitive buttons intended to be touched by a finger can often be triggered by quickly waving the palm of the hand close to the surface without touching.
Other types of touchscreen technologies include surface acoustic wave technology that uses ultrasonic waves, an infrared touchscreen panel, strain gauge panels coupled to springs, optical imaging, dispersive signal technology, and total internal reflection.
Electronic paper, also called e-paper, is a display technology designed to mimic the appearance of ordinary ink on paper. Electronic paper reflects ambient light similarly to ordinary paper, as opposed to a conventional flat panel display that uses a backlight to illuminate the pixels. Once a display image is painted on the display surface, electronic paper is capable of holding the display image indefinitely without drawing electricity. Electronic paper can be built using several different technologies, including, but not limited to, electrophoretic displays, electro-wetting displays, and cholesteric liquid crystal displays (LCD). Electronic paper produces a stable image using a relative low amount of power since the displayed image does not need to be refreshed and the displayed image is viewed without using a backlight. Applications include e-book readers capable of displaying digital versions of books, magazines, and other traditionally printed materials.